Blood collection tube with surfactant

ABSTRACT

Improvements in blood collection and testing. In one aspect, an improved method of manufacturing a blood collection tube, particularly illustrated for use in sedimentation rate testing, including providing an elongated glass tube with an open first end for receiving a venipuncture blood sample of at least 1 ml, formed with a closed end opposite the first end; and applying to a substantial portion of the receptacle a containment barrier. The improvements also pertain to resulting blood collection tubes, additives for blood collection tubes that permit reliable sedimentation test data after 8 hours from the blood draw, and methods of administering health care using the aforenoted tubes, additives or both.

CLAIM OF BENEFIT OF FILING DATE

The present application claims the benefit of the filing date of U.S.Provisional Application Ser. No. 60/660,284 (Filed Mar. 10, 2005), andthe entirety of the contents of this application being hereby expresslyincorporated by reference.

FIELD OF THE INVENTION

This invention relates to the collection, transport and analysis ofblood, and more particularly to a tube system for handling blood foranalysis of erythrocyte sedimentation rate (ESR).

BACKGROUND OF THE INVENTION

The ESR test measures the sedimentation rate of aggregated erythrocytesin plasma. The rate of sedimentation is an indirect means of analyzingRouleaux formation and aggregation of erythrocytes (red blood cells).Sedimentation rates tend to be an indicator of the presence, severity orboth of some pathological conditions, such as those associated withcertain disease states. Thus, the ESR test has been utilized as anindirect measure of these pathological conditions. Further, because ofthe simplicity of the test and materials for performing it, the ESR testhas enjoyed common usage in laboratories, including popularity not onlyat large-scale regional clinical laboratories (e.g., serving a number ofdifferent health care facilities), within hospitals or researchinstitutions, and even at local health care facilities (e.g., physicianoffices and clinics).

The history of ESR testing is relatively modern. Westergren developedthe technique of performing an ESR determination as described in AlfWestergren, “Die senkungscreaktion”, Ergegn. Inn. Med. Kinderheilk.,26:577 (1924). In the Westergren method, a venipuncture blood samplemixed with an anticoagulant (e.g., including a citrate) is placed atube. The tube is held vertically (e.g., in a rack) at room temperature,taking precautions to avoid direct sunlight, vibrations and drafts.After a time period (typically 1 hr), the distance (x) from the bottomof the resulting plasma meniscus to the top of the column of sedimentingred cells is read and the ESR value is derived (e.g., ‘ESR (Westergren 1hr)=x mm’). The Westergren method typically employs as its measuringtube a straight tube about 30 cm long and 2.5 mm in internal diameter,thus requiring about 1 mL of blood. A citrate diluent is commonlyemployed as well.

Other ESR techniques are also known, such as the modified Westergrenmethod. The Wintrobe method resembles the Westergren method, but tendsto employ a shorter measuring tube (12 cm long) and omits citratediluent from the tested blood. Historically, the Westergren and Wintrobetechniques have been manually performed. However, the techniques are nowemployed by semi-automated and automated instruments as well. In most ofthose instances, sophisticated optical detectors are employed.

As can be seen, the reliability and consistency of ESR testing can beaffected by any of a number of factors, not the least of which is thenature of the tube used for containing the blood sample. For example,delays in testing or potential exposure to contaminants thatdeleteriously alter the surface free energy of cells are possiblesources of error. It also has been recognized that variations of thenature of the measurement tube will affect test results. Specifically,it has been acknowledged that, even though plastics can be employed incertain procedures, the plastics are susceptible to (for example)plugging or plasticizer interaction with blood that are a potential forerroneous results; thus, standards prefer that blood be contained withina glass tube. See, e.g., CLSI Standard No. H2-A4, hereby expresslyincorporated by reference.

Unfortunately, despite the efficacy of glass and its preference as apreferred material, many laboratory practitioners prefer the use ofplastic, because of the lower risk of potential breakage andtransmission of blood-borne infection.

The medical community would benefit substantially if the advantages of aglass container could be secured in a test blood tube that is also moreresistant to fracture than traditional glass tubes, is capable ofcontaining fragments if a fracture occurs, is capable of containingblood if a fracture occurs, or any combination thereof.

The use of a wrapped capillary tube for hematocrit measurement (namelythe packed cell volume measurement of erythrocytes) of samples obtainedfrom finger-stick blood draws has been proposed in U.S. Pat. Nos.5,900,091 and 5,173,266 both expressly incorporated by reference for allpurposes. In those patents a sheet of polyester film with an adhesivelayer is wrapped over a small volume, thin diameter capillary tube(illustrated as having a volume of not more than 2 ml and an outsidediameter of about 0.060 inches). A clay plug helps contain blood withinthe capillary tube. The employment of tubes of this diameter has beencriticized in Clinical and Laboratory Standards Institute (“CLSI”;formerly NCCLS) Standard H2-A4, where it was also acknowledged that“[m]any so-called Westergren pipets, both glass and plastic, have aninternal diameter which is less than called for in this document, i.e.,less than 2.55 mm. Such pipets have been associated with spuriousresults, especially in specimens with a packed cell volume (PCV;“hematocrit”) greater than 0.35 (“35%”). Unfortunately, pipets adequatefor all blood specimens, including those with higher PCV, are not yetwidely available.” Accordingly, therefore, the selected proceduredescribed by CLSI specifically calls for dilution of the specimen beforemeasuring the sedimentation rate.

SUMMARY OF THE INVENTION

The present invention is predicated upon the discovery of improvementsto blood sedimentation rate testing. In one aspect, the inventionpertains to a method of manufacturing a tube for blood analysis,including the steps of providing an elongated glass tube with an openfirst end for receiving a blood sample of at least one ml, the tubebeing formed with a closed end (specifically an integral end that has athickness of about 0.5 to 1.0 mm) opposite the first end; and applyingto a substantial portion of the receptacle a containment barrier thatoptionally is sufficiently transparent that accurate and reproduciblesedimentation rate tests are obtainable by an optical detectiontechnique, and following a fracture of the tube, blood is containedwithin the tube. The present invention also contemplates a kit for bloodsedimentation rate testing that includes a glass tube formed with aclosed end and having an applied containment barrier thereon. In anotheraspect, the present invention is directed to a method for facilitatingthe performance of a blood analysis upon a sample of blood more than 8hours after the blood is drawn. The present invention also contemplatesblood collection tubes, glass or plastic, with or without a containmentbarrier, an additive that enables performance of a blood analysis upon asample of blood (e.g., a sedimentation rate analysis) more than 8 hoursafter the blood is drawn, yielding results comparable with freshly drawnblood.

DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B illustrate cross-sectional views of examples of tubesaccording to the present invention, respectively in an intact state anda broken state.

DETAILED DESCRIPTION

The present invention is predicated upon the discovery of improvementsto blood sedimentation rate testing. In one aspect, with reference tothe drawings, the invention pertains to a method of manufacturing a tubefor blood sedimentation rate analysis, including the steps of providingan elongated glass tube 10 with an open first end 12 for receiving ablood sample of at least one ml, the tube being formed with a closed end14 (specifically an integral end that has a thickness of about 0.5 to1.0 mm) opposite the first end; and applying to a substantial portion ofthe receptacle a containment barrier 16 that is sufficiently transparentthat accurate and reproducible sedimentation rate tests are obtainableby an optical detection technique, and following a fracture of the tube,blood is contained within the tube. In one specific embodiment, withreference to FIG. 1B, upon fracture the containment barrier maintainsall fragments in substantial longitudinal alignment. The containmentbarrier, the glass tube or both may have one or more visual indicators,such as one or a combination of a fill-line, a label, a bar code, atransmitter for a radiofrequency identification device (RFID) orotherwise.

The tubes of the present invention may be of any suitable length andvolume. One approach involves providing tubes of a volume ranging fromabout 1 ml to about 5 ml or larger. For example, the tubes of thepresent invention are particularly useful for receiving blood draws of1.2 ml or 2.0 ml. Accordingly, methods of the present inventioncontemplate using tubes with ESR test equipment available commercially,such as instruments available from Streck Laboratories, Inc. under thedesignations ESR-100™ or ESR-Auto Plus™. Under these methods, bloodsamples are collected (e.g., in an evacuated glass tube as describedherein). The samples are mixed with any additive contained within thetube. The sample is loaded in the test instrument (for example, withouttransferring to another tube), where sedimentation rate is monitored.After a pre-determined period of time, the results are outputted, e.g.,in a printed form, by a visual display device, onto an electronicstorage medium or any combination thereof. The results may be stored forlater retrieval in a suitable electronic medium. The results may betransferred from one site to another by way of an electronic network,such as the internet.

Tubes according to the present invention will typically be substantiallyoptically clear glass, and more specifically a USP Type III glass, suchas soda lime glass. Preferably the glass will include silica as a majorcomponent, e.g., about 70% by weight or higher. Calcium oxide (e.g.,from lime) and sodium oxide (e.g., from soda ash) may also be includedin amounts ranging, respectively from about 7 to about 12 parts byweight, and about 12 to about 18 parts by weight, where silica ispresent in about 70 parts by weight. Other additives may also beincluded, such as oxides of calcium, magnesium, or the like. Further,the density may range from about 0.085 to about 0.095 lbs/inch. Otherglasses are also possible, such as without limitation, borosilicateglasses including silica (about 70 to about 80% by weight) and boricoxide (about 7-13% by weight) with smaller amounts of the alkalis(sodium and potassium oxides) and aluminum oxide. The glass may also bea fused silica glass or another heat resistant glass that is high insilica content. It should be appreciated that certain embodiments of thepresent invention do not require that the tube be a glass material. Itis also possible that aspects of the present invention employart-disclosed plastic tubes.

With reference again to FIG. 1A, preferred tubes will have an overalllength (L), a glass wall thickness (T_(w)), a glass inside diameter(D_(IG)) and an overall outside diameter (D_(OO)). The containmentbarrier 16 will also have a thickness (T_(CB)). The overall length willtypically range from about 100 to about 300 mm (e.g., about 119 to about121 mm). The glass wall thickness will typically range from about 0.5 toabout 1.5 mm (e.g. about 0.9 to about 1.1 mm); at the closed end, thethickness might decrease relative to the side walls (e.g., to about 0.7mm relative to about 1 mm glass wall thickness in the side walls). Theglass inside diameter will range from about 4 to about 6 mm (e.g., about4.8 to 5.4 mm). The overall outside diameter will be about 5 to about 10mm, but more specifically will be less than about 9 mm (e.g., about 8mm). Thus, the containment barrier thickness will typically be less thanabout 1 mm (e.g., about 0.5 mm). Larger or smaller dimensions are alsopossible.

The containment barrier is such that it covers substantially theentirety of the outer surface of the tube, although it need not,provided that the coverage is sufficient that following a fracture ofthe tube, blood is contained within the tube. As discussed, among theadvantages derived from the present invention are the possibility that aclosed-end glass tube (e.g., soda lime glass), and particularly one intowhich the blood sample is directly drawn, can be made to perform as wellas preferred glass tubes as recommended by CLSI in Standard No. H2-A4,but they do not suffer the same potential risks associated withbreakage. In one aspect, this is the result of the employment of thecontainment barrier, for substantially encapsulating the elongated glasstube over its entire outer surface. The containment barrier preferablyincludes one or more applied layers, which may include a substantiallycontinuous layer, may include a plurality of apertures, may include amesh, weave, a sleeve, a winding or any combination thereof, or anycombination of the foregoing. Any such layers may be relatively inertrelative to blood, or it may contain one or more agents for interactingwith the blood upon contact therewith. For example, the containmentbarrier may carry an anti-microbial, an absorbent (e.g., a suitablepolymer, treated fiber or other absorbent material as discussed herein),a molecular sieve, or any combination thereof.

Application of the containment barrier to the tube may be done by any ofa number of different techniques including, for example, a step ofspraying, dipping, brushing, vapor depositing, wrapping, laminating,shrink-wrapping, any combination thereof or some other suitable surfacetreatment technique. It is possible that one or more intermediate layersmay be employed, such as a primer layer, an adhesive layer or anycombination thereof. A particularly preferred approach is to coat anelongated, closed end glass tube with a thin layer of a plastic (e.g.,by spraying, dipping or brushing) over its outer surface, its innersurface or both, for forming a containment barrier. In such instances,it is possible that a solution, emulsion or other dispersion thatincludes the plastic or a precursor is contacted with the glass tube forforming the containment barrier. For a shrink-fitting or shrink-wrappingapproach, it may be possible to employ a sheet of material that isplaced over the glass tube and then is shrunk to be intimately securedwith the tube. It may also be possible to employ a preformed casing(e.g., formed in the shape of one of the separable portions of a pillcapsule) that is slipped over the tube and then shrunk to be intimatelyjoined with the tube. Such fitting may also be accomplished by selectionof a material that differs in thermal expansion coefficient relative tothe glass, so that one or both of the casing or the tube can be heatedor cooled to accomplish a fit, and upon return to room temperature thecasing material will be placed in hoop tension about the tube.

The containment barrier will typically be a material, structure orcombination thereof that is sufficiently rigid that it will withstandrupture in the presence of load events sufficient to break the tube ifno barrier is present. Thus, as seen in FIG. 1B, one such structure andmaterial combination, though a load event (e.g., being dropped to a hardsurface from a distance of about 1 to about 3 meters, being stepped uponby a person weighing more than about 50 kg, a collision with anotherbody in motion, or otherwise) is sufficient to shatter the tube (e.g.,the load exceeds the ultimate tensile load of the tube material), thecontainment barrier contains the contents of the tube, including tubefragments, and may also, upon fracture the containment barrier, maintainall fragments in substantial longitudinal alignment. Typically, thecontainment barrier will be one or more relatively uniform outer layersthat substantially encapsulate the tube, such as that attainable bywrapping a film, or substantially uniformly applying the containmentbarrier layer as an at least partially hardenable liquid coating (e.g.,from a solution having a polymer dissolved or dispersed therein, from amelt, or otherwise).

The material selected for the containment barrier may be any suitablematerial. If it is to overlie substantially the entirety of the outersurface of the tube, the material typically will be a substantiallyamorphous ceramic, plastic, wax or combination thereof. Examples ofsuitable plastics include, without limitation, polythene naphthalate,cellulose acetate, polycarbonate (e.g., LEXAN®), polyethylene,polypropylene, poly-vinyl fluoride, polyimide, polyester (e.g., Mylar®,Melinex® or the like), polyamide (e.g., Nylon 6,6), polyvinyl chloride,combinations thereof or the like. Plastics may be treated so that theyhave a release coat (e.g., silicone), heat stability, an adhesiveapplied, a color coated, a moisture absorbent applied, an image (e.g., aholographic image), or otherwise treated to locally or uniformly modifya characteristic of the material. The plastics as used in thecontainment barrier preferably will be substantially transparent forfacilitating optical detection and monitoring of sedimentation rates.However, some crystallinity may be possibly. For example, it is possiblethat an axially oriented plastic is employed for helping provideenhanced mechanical properties.

The containment barrier may also be configured so that it is tamperevident (e.g., removal of the barrier reveals a visual or otherdetectable message or indicator), or another indicator is provided todenote it is not an unused tube. For example, a containment layer may beapplied on a tube that has been evacuated, has additives already presentor both, and which is sealed. The containment barrier would overly atleast part of the seal, thus hindering opening of the seal. Further thetube itself may be provided with an indicator to denote that it has acontainment barrier present. For example, the tube might carry oneportion of a message or indicator having two or more portions, such aspart of a word. The containment barrier would in turn be printed with orotherwise marked with the second part of the message. Thus when thecontainment barrier is present the portions of the message form acomplete message.

In one embodiment, the containment barrier of the present inventionfurther includes a tear strip, perforations or some other structure thatwould facilitate removal of the containment barrier so that it, thetube, the seal (e.g., a cap or possibly even the containment barrieritself) or any combination thereof could be recycled. The presentmethods thus contemplate a step of recycling within its scope.

The present invention also contemplates a kit for blood sedimentationrate testing that includes a glass tube formed with a closed end andhaving an applied containment barrier thereon. In another aspect, thepresent invention is directed to a method for facilitating the reliableperformance of a blood sedimentation rate upon a sample of blood morethan 8 hours after the blood is drawn.

In accordance with one embodiment, the present invention contemplatesthe manufacture of a blood collection tube for a sedimentation ratetest, pursuant to which a step of transferring blood from a conventionalblood collection tube into a separate tube for performing the test isavoided. Specifically, the blood collection tube serves not only as thereceptacle into which blood is immediately stored upon a patient draw,but also serves to carry the blood during the sedimentation rate test.In this manner, it is possible to reduce handling steps that are apotential source of test error and exposure to blood pathogens.

Under this approach, it is therefore contemplated at least one step ofevacuating the elongated glass tube to below atmospheric pressure andsealing the evacuated glass tube (e.g., with an art-disclosed cap). Suchapproaches to evacuation and sealing are disclosed, for example, inpublished U.S. patent Application No. 20040137417 (Ryan), herebyincorporated by reference. Further, whether an evacuation step isemployed or not, it is possible that the tubes will be prepared so thatupon receipt thereof, a user (e.g., a medical practitioner or othertechnician), the tubes will contain an additive (typically in a liquidform, but which may be solid or semi-solid (e.g., a gel, cream orpaste)). It will be appreciated that one advantage of the presentinvention is that it permits for the use of dry additives and wetadditives, unlike plastic tubes which typically require dry additives,in view of the propensity for moisture loss inherent with a plastictube.

Therefore the method may further include a step of introducing into thetube, prior to introducing any blood, an additive selected from thegroup consisting of a preservative, an anticoagulant, an antimicrobial,a surfactant, or any combination thereof. More particularly, the methodmay further include a step of introducing into the tube, prior tointroducing any blood, a surfactant and an additive selected from thegroup consisting of a preservative, an anticoagulant, an antimicrobial,or any combination thereof. Examples of additives generally aredisclosed, without limitation in Tubes according to the presentinvention preferably satisfy the criteria set forth in Annex E of ISO6710: 1995(E) for “Single-use containers for venous blood specimencollection”, incorporated by reference. Examples of anti-coagulantadditives include, without limitation, an anticoagulant agent selectedfrom the group consisting of ethylene diamine tetra acetic acid (EDTA),salts of EDTA, ethylene glycol tetra acetic acid (EGTA), salts of EGTA,hirudin, heparin, citric acid, salts of citric acid, oxalic acid, saltsof oxalic acid (e.g., potassium oxalate, sodium oxalate, or the like),and a combination thereof. They may be present in sufficient artdisclosed amounts. For example, one approach is to employ as ananti-coagulant an aqueous combination of trisodium citrate, and citricacid, monohydrate wherein the relative amount (by weight) of trisodiumcitrate, dehydrate to citric acid, monohydrate is about 5:1 to about12:1, and more specifically is about 8:1.

An example of a suitable anti-microbial includes, for example, sodiumazide thimerosal, chloramphenicol, 5 bromo-5 nitro 1,3 dioxane,tetradecyltrimethylammonium bromide or the like in their art-disclosedamounts.

Additional additives may optionally be added in the tubes. Suchadditional and optional compounds may include, without limitation, cellpermeabilizing agents for substantially gaining access to intracellularanalytes/epitopes and/or for lysing red blood cells; proteins thatsubstantially protect the cells during processing and/or substantiallyreduce non-specific binding of probes; serum/lipoproteins thatsubstantially protect cells during processing and/or substantiallyreduce non-specific binding of probes; RNAse inhibitors whichsubstantially inhibit digestion of RNA and/or substantially maintain RNAintegrity; nucleic acid stabilizers which substantially inhibit thedegradation of nucleic acids and nucleic acid containing compounds;amino acids/polypeptides which substantially enhance binding ofprobes/antibodies to epitopes and/or substantially increases theobservable signal; fixatives which substantially preserve cell integrityespecially for permeabilization agents, and may preserve some epitopes;anticoagulants which substantially decreases clotting of red bloodcells, chelates calcium and/or may help maintain WBCintegrity/viability; protease inhibitors which substantially decreasesdegradation of protein epitopes; antioxidants/reducing agents whichsubstantially prevent hemolysis of red blood cells and/or substantiallyprevent oxidation of peptides, and/or substantially maintain epitopes;nucleic acid dyes that generally serve to label/identify nucleic acid;carbohydrates which substantially maintain cellular integrity and/orosmolarity; and, polyacrylic acids which substantially enhance thebinding of probes and/or antibodies to epitopes; and/or substantiallyincreases signal. One of skill in the art should be able to determinethe usefulness and quantities of such optional compounds by routinetesting and knowledge of the art. Within the above, particular examplesof additives include, without limitation, Cell permeabilizing agentssuch as: DMSO (Dimethyl Sulfoxide), Ethylene glycol, Polyethyleneglycol, Glycerin, Cellosolves (ethylene glycol dimethyl ether)(phenoxyethanol), Triton® X 100, Triton® X 705 (non-ionic detergents),1-methyl-2-pyrrolidinone, Tween® 20, Tween® 40 (non-ionic), Brij® 35(detergent), Polyoxyethylene ether (Polyox), Sodium cholate, Ethyleneoxide polymers, Monensin, Monactin, Pentachlorophenol, 2,4dinitrophenol, saponin, SDS (sodium dodecyl sulfate); Proteins such as:Biotin, Albumins (egg, bovine), Gelatin, and similar such compounds asshould be known to one of skill in the art; RNAse inhibitors such as:human placenta derived RNAse inhibitor, and similar such compoundsshould be known to one of skill in the art; Nucleic acid stabilizerssuch as: Guanidinium hydrochloride, Polycations such asPolyethylenimine), and similar such compounds as should be known to oneof skill in the art; Amino acids/polypeptides such as: Glutamic acid,Glycine, Aspartic acid, and similar such compounds as should be known toone of skill in the art; Fixatives such as: Aldehydes (formaldehyde andglutaraldehyde), Alcohols (ethanol, methanol), and similar suchcompounds as should be known to one of skill in the art; Anticoagulantssuch as: EDTA (Ethylene Diamine Tetra acetic acid.), and similar suchcompounds as should be known to one of skill in the art; ACD (AcidCitrate Dextrose), Heparin, and similar such compounds as should beknown to one of skill in the art; Protease Inhibitors such as: EDTA,PMSF (phenyl methyl sulfonyl fluoride), AEBSF (2-Aminoethyl benzenesulfonyl fluoride), and similar such compounds as should be known to oneof skill in the art; Antioxidants/Reducing agents such as: Trolox,a-tocopherol, B-mercaptoethanol, and similar such compounds as should beknown to one of skill in the art; Nucleic Acid Dyes such as: DAPI(Diamidino 2-phenylindole), Propidium Iodide, Fluorescein diacetate, andsimilar such compounds as should be known to one of skill in the art;Carbohydrates such as: Sugars (sucrose), cellulose, and similar suchcompounds as should be known to one of skill in the art. It should beappreciated that the above specific listings of compounds may contain ameasure of overlap, which recognizes the sometimes-overlapping functionof certain specific compounds. One of skill in the art should understandand appreciate this aspect of the disclosure.

In another aspect of the present invention, methods of using the tubesand kits of the present invention contemplate the stabilization of oneor more of the components of a blood sample so that sedimentation ratetesting, though it may occur substantially contemporaneously with theblood draw, alternatively or additionally may occur (in a consistent andreproducible manner that approximates that of a fresh blood sample)after a delay of more than about 12 hours, and more specifically morethan about 24 hours (e.g., after a period of 36, 48, 60, 72 hours ormore have elapsed). One embodiment contemplates a period of at least 4days between the time of the blood draw and sedimentation rate testing.In this manner, it is possible to offer sedimentation rate test blooddraw services to remotely located populations, where sedimentation ratetest equipment may be unavailable, and thereafter to transport the drawnblood to a remote location for subsequent analysis (whether contained inthe tube or removed from the tube during or for analysis), withoutcompromising the blood sample.

With reference to the above step of transporting the blood, and as forany other handling steps that may occur prior to testing, the presentinvention also contemplates that the blood sample may be kept at ambienttemperature (e.g., about room temperature), raised or lowered relativeto ambient, or any combination thereof. For example, a portable heateror refrigeration device (e.g., a solid state thermoelectric device) maybe used for storing blood. One specific approach contemplatesmaintaining the temperature of the sample below about 20° C., and morespecifically below about 15° C. (e.g., about 2 to about 10° C.).

Without intending to be bound by theory, it is believed that theemployment of a particular additive selection in the tube contributes tostabilization of the sample so that substantial delays (e.g., for aperiod of at least about two hours longer than what would be obtainablefor a fresh whole blood without the particular additive selection) maytake place between the time of the blood draw and the time ofsedimentation rate testing. In particular, it is believed that theemployment of a surfactant in the additive selection helps contribute tothis advantage. Though other surfactants are possible, includingcationic, anionic, Zwitterionic or any combination thereof, a specificexample of a class of surfactants for the present invention is nonionicsurfactants.

More particularly, the nonionic surfactants of the present invention areselected to have an average monomer molecular weight in the range ofabout 500 to about 2000, and more specifically about 800 to about 1600,and still more specifically about 1100 to about 1400 (e.g., about 1200).Further, the surfactant will have an aggregation number that ranges fromabout 20 to about 120 (e.g., about 40). The surfactant typically will beof substantially homogeneous purity. The surfactant preferably is freeof clouding under the conditions to which it will be exposed prior toand during sedimentation rate testing.

A preferred group of surfactants typically include a hydrophobic moiety(e.g., an alkyl chain) in combination with a hydrophilic moiety (e.g., apolyoxyethylene chain), and further may include an ether linkage, forexample a surfactant based upon polyoxyethylene alkyl ether. In oneembodiment, the nonionic surfactant is one of the form C_(x)E_(y), wherex is the number of carbons in the alkyl chain (C) and y is the number ofethylene oxide units in the polyoxyethylene chain (E). In this respectspecific examples will employ an x value ranging from about 6 to about18 (e.g., about 12) and a y value ranging from about 4 to about 40(e.g., about 23).

Thus, it is possible that the surfactants are based upon polyoxyethylenealcohols, polyoxyethylene alkylphenols, or a combination thereof, andparticularly surfactants of such type having one or more ether linkages.Examples of specific surfactant ingredients include, without limitation,polyoxyethylene (20) sorbitan monolaurate, polyoxyethylene (23) laurylether, polyoxyethylene (9) mono(octylphenyl)ether, polyoxyethyleneoctylphenyl ether, or any combination thereof. Specific commercialexamples include, without limitation, Tween® 20, Tween® 40, Tween®80,Brij® 30, Brij® 35, Brij® 58, Triton® X-100, Triton® X-114, Triton®X-705, or any combination thereof.

Of course, it may be possible to employ any of a number of othersurfactants, such as the organosilicone surfactant (namelypolyalkyleneoxide modified polydimethylsiloxane) disclosed in U.S. Pat.Nos. 5,914,272 and 5,779,983 (hereby incorporated by reference),alcohols, esters of fatty acids, mercaptans, and alkylamines; nonionicsurfactants containing an amide group; polyol ester surfactants or anycombination thereof.

The amount of the surfactant that is employed is preferably such that ifthe surfactant clouds, then the amount of clouding will not impair theability to monitor the sedimentation rate. It is also used in sufficientamount that it is capable of providing reproducible sedimentation ratetests (in a consistent and reproducible manner that approximates that ofa fresh blood sample) after a delay of more than about 12 hours, andmore specifically more than about 24 hours (e.g., after a period of 36,48, 60, 72 hours or more have elapsed), and optionally when the bloodsample is maintained at ambient temperature (though it may berefrigerated or heated as described herein). One embodiment contemplatesusage of the surfactant in an amount that a sedimentation rate testapproximating that of fresh blood is obtained after a period of at least4 days between the time of the blood draw and sedimentation ratetesting. Examples of concentrations typically will range from about 0.1g/l to about 5 g/l, more specifically about 0.5 g/l to about 3 g/l, andstill more specifically about 0.9 to about 1.5 g/l (e.g., about 1.0g/l). In another approach, the concentration of the surfactant is lessthan about 10% of the concentration of the anti-coagulant, and morespecifically is less than about 5% of the concentration of theanti-coagulant.

The total amount of additive in the tube will vary as desired. However,for blood draws of about 1 to 2 ml, it is preferred that the amount notexceed about 25 to about 60% of the total resulting volume (namely,additive plus blood sample). For example, with a tube drawing havingabout 1.2 ml of blood, about 0.34 ml of additive will be present. For atube drawing having about 2.0 ml of blood, about 0.56 ml of additivewill be present.

The tubes of the present invention may be included in a kit adapted forcollection, transport, or analysis of the drawn blood sample. Examplesof components that might be part of such a kit include, withoutlimitation an alcohol swab, gauze, a tube holder, a tube rack, atourniquet, a glove, another cell collection tube (with or withoutconventional cell analysis additives inside such tube), needle (withhub, part of a syringe assembly including barrel and plunger, or withwings connected via a hub and tubing to another needle for delivery tothe device 100 or other collection tubes), lancet, adhesive strip,syringe, test strip (allowing the blood to flow directly onto a glass orplastic strip containing reagents for cell analysis), glass or plasticstrip containing reagents for cell analysis (e.g., immunoassay),packaging (e.g., plastic bag, compartmentalized plastic enclosure, andthe like) to store the desired components, packaging to transport theblood sample stored in the tube after collection, a timer, a worksheet(e.g., for recording sedimentation levels at different times), or anycombination thereof. It is preferred that any components that may comein physical contact with the blood sample be sterilized and that thepackaging is constructed to substantially maintain this sterileenvironment.

The packaging may also include a suitable moisture absorbent forabsorbing blood in the event of spillage, such as a mass of absorbentmaterial that is contained within at least a partially moisturepermeable covering. The absorbent material may include a cellulosicmaterial, (e.g., cotton, wood pulp, or the like) that is optionallymodified or cross-linked. Synthetic materials may also be used, such asart-disclosed super-absorbent polymers or gels, plastic (e.g.,polyolefin or polyester) fibers, absorbent foams. The absorbent materialmay also be of a suitable structure for enhancing absorptioncharacteristics, such as capillary channel structures, structures withlarge surface areas for enhancing absorption, surface treated structuresor any combination thereof. Any combinations of the foregoing materialsmay also be used, such as a super-absorbent polymer, combined with awood pulp including co-formed fibrous structures.

The present invention also contemplates methods of administering healthcare diagnosis or treatment to remote populations. For example, one suchmethod contemplates coordinating the delivery of a cell (e.g., a bloodcell) sampling kit to at least one remote location, where a blood sampleis drawn from a plurality of persons and is analyzed more than 12 (andmore specifically more than 24 hours, and even up to at least 4 days)after each sample is drawn. Information is received about results of ananalysis (e.g., an ESR or ZSR analysis) of the patient sample.Administration of a pharmacological therapy (which optionally mayinclude a generic drug) to a plurality of such persons whose sampleindicates treatment is necessary is then performed. Any or all of thesteps of coordinating delivery, receiving information and administrationof therapy can all be performed from a site that is remote from the siteof the patient blood draw. Another aspect of these methods contemplatescoordinating the transport of the sample from the blood draw site to thesite where it is analyzed. The transport may take place in ambientconditions or the sample may be heated or refrigerated, such as bycontaining it within a portable solid state thermoelectric device. Thepresent invention therefore provides advantages over conventional healthcare methods, by enabling reliable blood testing to be obtained inregions where health care workers may not otherwise have access toappropriate instrumentation, but need to rely upon a remote analysis fordiagnosis. The invention thus can be employed in diagnosing, treating ormonitoring not only traditional conditions for which sedimentation ratetesting has been done (e.g., acute and chronic inflammation, infections,cancers, and various autoimmune diseases), but in connection with othertests as described herein (e.g., blood draws for flow cytometry or otherhematological analysis, such as might be used to diagnose, treat ormonitor cancer, HIV or some other condition).

Aspects of the present invention are not limited to sedimentation ratetesting. For example, it is possible that conventional closed endedblood collection tubes may be adapted to have a containment barrier. Inthis regard, other additives may be included as well, such as a fixativeselected from the group consisting of: diazolidinyl urea, imidazolidinylurea, dimethoylol-5,5dimethylhydantoin, dimethylol urea,2-bromo-2.-nitropropane-1,3-diol, oxazolidines, sodium hydroxymethylglycinate, 5-hydroxymethoxymethyl-1-1aza-3,7-dioxabicyclo [3.3.0]octane,5-hydroxymethyl-1-1aza-3,7dioxabicyclo [3.3.0]octane,5-hydroxypoly[methyleneoxy]methyl-1-1 aza-3, 7dioxabi cyclo[3.3.0]octane, quaternary adamantine and combinations thereof. In thisregard, the blood may be analyzed by one or more other automatedhematology analyzers, such as a flow cytometer. Further it is possiblethat the same blood sample that undergoes a sedimentation rate test maythen be diluted and analyzed for at least one other test by an automatedinstrument.

The following examples further illustrate aspects of the presentinvention.

EXAMPLE 1

A blood sample is drawn by venipuncture from a patient and is capturedimmediately upon drawing by a previously evacuated soda lime glass tubeto which a layer of MYLAR® film is coated over its exterior. The glasstube contains the ingredients of TABLE 1. After refrigeration for 12hours at a temperature varying between 2 and 10° C., the sample isrepeatedly tested by the Westergren method at intervals of two hours forthe following two days. Consistent results are observed over the periodof 12 to 72 hours from blood draw.

ADDITIVE COMPOSITION per liter % w/v Trisodium Citrate, dihydrate 32 g3.2 Anti-coagulant Citric Acid, monohydrate 4.2 g 0.42 Anti-coagulantSodium Azide 0.50 g 0.05 Anti-microbial Brij  ® 35 1.0 g 0.10 Surfactant

EXAMPLE 2

Example 1 is repeated, except the glass tube has no barrier layer. Theblood tested shows the same sedimentation rate as the glass tube withthe barrier layer. However, upon dropping to the ground the glassfractures and blood spills.

EXAMPLE 3

Examples 1 and 2 are repeated, except that the surfactant is excludedfrom the additives. Testing performed at two hour intervals show thatafter about 6 hours, inconsistent results are thereafter obtained, witha gradual and substantially continuous change of sedimentation rateduring the period following 12 to 72 hours from blood draw.

Blood drawn and handled in accordance with the present invention may beanalyzed by any of a number of different techniques, such as aredisclosed in CLSI Standard No. H2-A4, hereby expressly incorporated byreference, including without limitation, the Westergren method oferythrocyte sedimentation rate testing, modified Westergren method oferythrocyte sedimentation rate testing, the Wintrobe method oferythrocyte sedimentation rate testing, Zeta Sedimentation RatioDetermination (ZSR) using centrifugation, or otherwise. The tests may beperformed manually, or using a semi-automated or automated instrument.

The methods herein contemplate steps of using tubes according to thepresent invention in a clinical laboratory for diagnosis of a condition,for monitoring a response of a patient to therapy, for monitoringquality and operation of a measurement instrument or system, forcalibrating a measurement instrument or system, or any combinationthereof.

Tubes according to the present invention preferably satisfy the criteriaset forth in ISO 6710: 1995(E) for “Single-use containers for venousblood specimen collection”. Accordingly, users of the present inventioninclude, without limitation, clinical laboratory personnel,manufacturers of instruments or systems, distributors of instruments orsystems, manufacturers of tubes, distributors of tubes, or otherwise.

It will be further appreciated that functions or structures of aplurality of components or steps may be combined into a single componentor step, or the functions or structures of one step or component may besplit among plural steps or components. For example, the containmentbarrier might be divided into plural components for performing thefunctions described. Alternatively, functions performed by one of thecomponents might be split among or performed by other components (e.g.,a tempering or other heat treating process may be employed with glass sothat upon fracture, the fracture occurs in a predetermined manner). Thepresent invention contemplates all of these combinations. Unless statedotherwise, concentrations, amounts, dimensions and geometries of thevarious structures depicted herein are not intended to be restrictive ofthe invention, and others are possible. References to “blood” hereingenerally pertain to human blood. However, the present invention is notintended to be limited only to human blood. Blood of other mammals andother animals may also be handled or otherwise processed using thepresent invention. In addition, while a feature of the present inventionmay have been described in the context of only one of the illustratedembodiments, such feature may be combined with one or more otherfeatures of other embodiments, for any given application. It will alsobe appreciated from the above that the fabrication of the uniquestructures herein and the operation thereof also constitute methods inaccordance with the present invention.

The explanations and illustrations presented herein are intended toacquaint others skilled in the art with the invention, its principles,and its practical application. Those skilled in the art may adapt andapply the invention in its numerous forms, as may be best suited to therequirements of a particular use. Accordingly, the specific embodimentsof the present invention as set forth are not intended as beingexhaustive or limiting of the invention. The scope of the inventionshould, therefore, be determined not with reference to the abovedescription, but should instead be determined with reference to theappended claims, along with the full scope of equivalents to which suchclaims are entitled. The disclosures of all articles and references,including patent applications and publications, are incorporated byreference for all purposes. Other combinations are also possible as willbe gleaned from the following claims, which are also hereby incorporatedby reference into this written description.

1-11. (canceled)
 12. A kit for performing a blood sedimentation rateanalysis, comprising: a) a substantially optically clear glass tubehaving an overall length of about 100 to about 300 mm and a wallthickness of about 0.5 to about 1.5 mm, and having a plastic containmentbarrier with a thickness of less than about 1 mm and a closed end, andcontaining an additive including a surfactant that is free of cloudingunder the conditions to which it will be exposed prior to and duringsedimentation rate testing and at least one additional additive selectedfrom the group consisting of an anti-microbial, and anti-coagulant, apreservative, or any combination thereof; and b) at least two componentsfor performing a blood sedimentation rate analysis selected from analcohol swab, gauze, a tube holder, a tube rack for performing a bloodsedimentation rate analysis, a tourniquet, a glove, another cellcollection tube, needle, lancet, adhesive strip, syringe, test strip,glass or plastic strip containing reagents for cell analysis, packagingto store the desired components, packaging to transport the blood samplestored in the tube after collection, a timer, a worksheet, or anycombination thereof.
 13. The kit of claim 12, wherein the surfactant ispresent in sufficient amount that it is capable of providingreproducible sedimentation rate tests in a consistent and reproduciblemanner that approximates that of a fresh blood sample after a delay ofmore than about 6 hours.
 14. The kit of claim 13, wherein the surfactantis a nonionic surfactant of the form C_(x)E_(y), where x is the numberof carbons in the alkyl chain (C) and y is the number of ethylene oxideunits in the polyoxyethylene chain (E).
 15. The kit of claim 14, whereinx is from about 6 to about 18 and y is from about 4 to about
 40. 16. Ablood collection tube for sedimentation rate analysis, comprising: anevacuated and sealed elongated glass tube with an open first end forreceiving a venipuncture blood sample of at least 1 ml, formed with aclosed end opposite the first end; a plastic containment barrier that issubstantially transparent and substantially encapsulates the elongatedglass tube so that following a fracture of the tube, blood is containedwithin the tube; and a surfactant, based upon polyoxyethylene alcohols,polyoxyethylene alkylphenols, or a combination thereof, being present insufficient amount that it is capable of providing reproduciblesedimentation rate tests in a consistent and reproducible manner thatapproximates that of a fresh blood sample after a delay of more thanabout 6 hours, and that is free of clouding under the conditions towhich it will be exposed Prior to and during sedimentation rate testing.17. The blood collection tube of claim 16, wherein the surfactant is anonionic surfactant of the form C_(x)E_(y), where x is the number ofcarbons in the alkyl chain (C) and y is the number of ethylene oxideunits in the polyoxyethylene chain (E).
 18. The blood collection tube ofclaim 17, wherein x is from about 6 to about 18 and y is from about 4 toabout
 40. 19. The blood collection tube of claim 18, wherein thesurfactant is present in a concentration of about 0.1 g/l to about 5g/l, the surfactant is selected to have an average monomer molecularweight in the range of about 500 to about 2000, and the surfactant willhave an aggregation number that ranges from about 20 to about 120; andfurther comprising at least one additional additive selected from thegroup consisting of an anti-microbial, and anti-coagulant, apreservative, or any combination thereof.
 20. The blood collection tubeof claim 19, wherein the surfactant is present such that a sedimentationrate test approximating that of fresh blood is obtained after a periodof at least 4 days between the time of the blood draw and sedimentationrate testing.
 21. A method for performing an erythrocyte sedimentationrate analysis, comprising: drawing a venipuncture blood sample into anevacuated and sealed elongated glass tube with an open first end and aclosed end opposite the first end, the elongated glass tube including acontainment barrier that is substantially transparent and substantiallyencapsulates the elongated glass tube so that following a fracture ofthe tube, the blood sample is contained within the tube; contacting theblood sample with a surfactant in the glass tube, the surfactant beingfree of clouding under the conditions to which it will be exposed priorto and during sedimentation rate testing; and performing the erythrocytesedimentation rate analysis while the blood sample is contained withinthe tube.
 22. The method of claim 21, wherein the surfactant is anonionic surfactant of the form C_(x)E_(y), where x is the number ofcarbons in the alkyl chain (C) and y is the number of ethylene oxideunits in the polyoxyethylene chain (E).
 23. The method of claim 22,wherein x is from about 6 to about 18 and y is from about 4 to about 40.24. The method of claim 23, wherein the surfactant is present in aconcentration of about 0.1 g/l to about 5 g/l, the surfactant isselected to have an average monomer molecular weight in the range ofabout 500 to about 2000, and the surfactant will have an aggregationnumber that ranges from about 20 to about 120;
 25. The method of claim21, wherein the surfactant is selected from polyoxyethylene (20)sorbitan monolaurate, polyoxyethylene (23) lauryl ether, polyoxyethylene(9) mono(octylphenyl)ether, polyoxyethylene octylphenyl ether, or anycombination thereof.
 26. The method of claim 21, wherein the surfactantis selected from organosilicone surfactants, alcohols, esters of fattyacids, mercaptans, and alkylamines; nonionic surfactants containing anamide group; polyol ester surfactants or any combination thereof
 27. Themethod of claim 22, further comprising contacting the blood sample inthe tube with at least one additional additive selected from the groupconsisting of an anti-microbial, and anti-coagulant, a preservative, orany combination thereof.